Commit Graph

7 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
6ed4c6af97 Rename virtRegMap to avoid confusion with the VirtRegMap that it isn't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120846 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-03 22:25:09 +00:00
Jakob Stoklund Olesen
5daec2215b Coalesce debug locations when possible, causing less DBG_VALUE instructions to
be emitted.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120845 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-03 22:25:07 +00:00
Jakob Stoklund Olesen
42acf069c9 Emit DBG_VALUE instructions from LiveDebugVariables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120842 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-03 21:47:10 +00:00
Jakob Stoklund Olesen
8d2584a1d9 Also update virtRegMap when renaming virtual registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120841 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-03 21:47:08 +00:00
Jakob Stoklund Olesen
30e2128a73 Update LiveDebugVariables during coalescing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120720 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-02 18:15:44 +00:00
Jakob Stoklund Olesen
0613516b16 Implement the first half of LiveDebugVariables.
Scan the MachineFunction for DBG_VALUE instructions, and replace them with a
data structure similar to LiveIntervals. The live range of a DBG_VALUE is
determined by propagating it down the dominator tree until a new DBG_VALUE is
found. When a DBG_VALUE lives in a register, its live range is confined to the
live range of the register's value.

LiveDebugVariables runs before coalescing, so DBG_VALUEs are not artificially
extended when registers are joined.

The missing half will recreate DBG_VALUE instructions from the intervals when
register allocation is complete.

The pass is disabled by default. It can be enabled with the temporary command
line option -live-debug-variables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120636 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-02 00:37:37 +00:00
Jakob Stoklund Olesen
bb7b23f5b7 Stub out a new LiveDebugVariables pass.
This analysis is going to run immediately after LiveIntervals. It will stay
alive during register allocation and keep track of user variables mentioned in
DBG_VALUE instructions.

When the register allocator is moving values between registers and the stack, it
is very hard to keep track of DBG_VALUE instructions. We usually get it wrong.
This analysis maintains a data structure that makes it easy to update DBG_VALUE
instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120385 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 02:17:10 +00:00